JPH0225276Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a shield structure for electronic circuits such as hybrid ICs.

[Conventional technology]

Conventional hybrid ICs having structures shown in FIGS. 4 and 5 are known. In the figure, 1 is a wiring board, and one side thereof is equipped with a plurality of lead pins 2a, 2b, 2c, . . . , 3a, 3
Reference numerals b and 3c are individual circuit components such as transistors, resistors, and capacitors, which are mounted on the wiring board 1.

4 is an insulating layer covering the surface of the wiring board 1 including the circuit component 3, and 5 is a conductive layer for shielding formed on the surface of the insulating layer 4.

When shielding a hybrid IC with such a structure, it is necessary to establish electrical continuity between the conductive layer 5 and the shield conductive layer 5 with one of the plurality of lead pins 2 that corresponds to the ground pin. A shield structure has been formed by providing a conductive layer 6 between the two and covering them by means such as taping.

[Problem that the invention attempts to solve]

When forming a shield structure in this way,
There is a problem in that it takes time and effort to perform masking work to partially cover areas where it is not desired to form a conductive layer, and an increase in costs is unavoidable.

[Means for solving problems]

The present invention has been made in response to the above problems, and it is an object of the present invention to provide a shield structure for electronic circuits that can be formed by a simple masking operation.

To achieve this object, the present invention provides an electronic circuit in which a predetermined circuit element is mounted on a wiring board having a plurality of lead pins, and the surface of the wiring board including the circuit element is covered with an insulating layer. A conductive layer connecting the shield conductive layer and a predetermined lead pin is formed while other lead pins are covered by a jig equipped with an exposure window that exposes only a predetermined lead pin. The present invention provides a shielding structure for electronic circuits.

[Effect]

According to the above configuration, a conductive layer for shielding is provided on the insulating layer on the surface of the wiring board while the lead pins are covered with a jig having an exposure window that exposes only a predetermined portion of the lead pins. Since the conductive layer for connecting the conductive layer and the conductive layer for connecting the predetermined lead pins are formed at the same time, a shield structure for the IC circuit can be obtained by a simple masking operation.

〔Example〕

The present invention will be explained below with reference to the drawings.

FIG. 1 is a perspective view showing the shielding structure of an electronic circuit according to an embodiment of the present invention. The same parts as in FIG. It is provided with an exposure window 8 that exposes. By covering the plurality of lead pins 2 with this jig 7 and applying a dip treatment in a solution of a conductive material, a shielding layer is formed on the predetermined lead pins exposed through the exposure window 8 and the insulating layer on the surface of the wiring board 1. A conductive layer 5 and a conductive layer 6 connecting the conductive layer 5 and the predetermined lead pins are easily formed.

FIG. 2 shows the arrangement before the jig 7 is inserted into the lead pin 2, and 9 is a groove for inserting the lead pin.

FIG. 3 shows a mode in which a conductive layer 6 is actually formed on a wiring board 1, and shows a common lead frame 10.
By applying a jig 7 each having an arbitrary exposure window to a plurality of wiring boards 1 that are integrally arranged on the wiring board 1, predetermined lead pins and wiring boards 1 can be attached.
The surface conductive layer 5 and the conductive layer 6 can be formed at the same time.

The means for forming the conductive layers 5 and 6 is not limited to deep treatment, but other means such as plating can also be used, and in short, any means can be selected as long as it is capable of forming conductive layers. can.

[Effect of idea]

According to the present invention as described above, the conductive layer for shielding and the conductive layer are coated on the surface of the wiring board with the lead pins covered by a jig equipped with an exposure window that exposes only a predetermined portion of the lead pins. Since the conductive layer connecting the layer and the predetermined lead pin is formed at the same time, the masking work can be completed simply by inserting the jig into the lead pin, which saves time and effort.

As a result, work becomes more efficient and costs can be reduced.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are top and perspective views showing an embodiment of the present invention, and Figures 4 and 5 are
The figures are a sectional view and a top view showing a conventional example. DESCRIPTION OF SYMBOLS 1... Wiring board, 2... Lead pin, 3... Circuit component, 4... Insulating layer, 5, 6... Conductive layer, 7...
...Jig, 8...Exposure window, 9...Cassette tape insertion slot.

Claims (1)

[Scope of utility model registration request] In an electronic circuit in which a predetermined circuit element is mounted on a wiring board having a plurality of lead pins, and the surface of the wiring board including the circuit element is covered with an insulating layer, there is a method in which only the predetermined lead pins are exposed. A shield structure for an electronic circuit, characterized in that a conductive layer connecting a shielding conductive layer and a predetermined lead pin is formed with other lead pins covered by a jig with an exposed window.